Veritas Volume Manager 5.0 Administrator's Guide (September 2006)

327Administering volume snapshots
Creating instant snapshots
For more information on the application of cascaded snapshots, see “Cascaded snapshots”
on page 304.
Refreshing an instant snapshot
Refreshing an instant snapshot replaces it with another point-in-time copy of a parent
volume. To refresh one or more snapshots and make them immediately available for use,
use the following command:
# vxsnap [-g diskgroup] refresh snapvolume|snapvolume_set \
source=volume|volume_set [[snapvol2 source=vol2]...] \
[syncing=yes|no]
If the source volume is not specified, the immediate parent of the snapshot is used. For
full-sized instant snapshots, resynchronization is started by default. To disable
resynchronization, specify the
syncing=no attribute. This attribute is not supported for
space-optimized snapshots.
Note: The snapshot being refreshed must not be open to any application. For example, any
file system configured on the volume must first be unmounted.
It is possible to refresh a volume from an unrelated volume provided that their sizes are
compatible.
You can use the
vxsnap syncwait command to wait for the synchronization of the
snapshot volume to be completed, as shown here:
# vxsnap [-g diskgroup] syncwait snapvol
See “Controlling instant snapshot synchronization” on page 333 for more information.
Reattaching an instant snapshot
Note: This operation is not supported for space-optimized instant snapshots.
Using the following command, some or all plexes of an instant snapshot may be
reattached to the specified original volume, or to a source volume in the snapshot
hierarchy above the snapshot volume:
# vxsnap [-g diskgroup] reattach snapvolume|snapvolume_set \
source=volume|volume_set [nmirror=number]
By default, all the plexes are reattached, which results in the removal of the snapshot. If
required, the number of plexes to be reattached may be specified as the value assigned to
the nmirror attribute.